chief
National Hazard
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elemental manganese ~ from MnO2, best route
I checked, and there doesn't seem to be a thread on this:
How can elemental Manganese be obtained ?
==> The thermite-Method works inefficiently, as I tried: Only 10 % of the theoretical amount will be found in the residuals, the rest goes into the
air due to the low vaporization-temperature of Mn around 2061 [Cels] ...
==> Electrolysis is said to be difficult ... but possible ..., strongly depending on the "right" conditions ...
Technically it's done with a semi-continuous thermite-reaction, where just as much thermite is added in small batches as to keep the temperature low
enough, so that not everything evaporates ...
==> Problem is the separation of Mn (boiling point 2061 [Cels]) from the Al2O3 (melting point 2100 [Cels]) ...
======================
MnO2 is the best available source: How should it be converted/reduced to obtain the pure metal ? Which of the salts can be best elctrolyzed ? How to
obtain the carbonate ?
==> I once did test-react MnO2 with some HNO3 (in a stirrer, for quite a while), and as I remember the ready solution then gave a ppt. with Soda
... which would have been the insoluble manganese-carbonate ..., but I didn't check it ...
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The WiZard is In
International Hazard
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Chemical Stunts With Chromium and Manganese
Popular Science February, 1935
http://tinyurl.com/34j5hgx
Be careful with this in my single experience with this
a whole bunch of years ago when I heated (strongly)
from the bottom a steel container of MnO2 and aluminium
it went POOOOF and burn a little bit of the hair on
top of my head. Had I been a little closer ....!
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not_important
International Hazard
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Which is why the thermite process generally uses a lower oxide such as Mn2O3 or Mn3O4, with MnO2 just in the starting booster.
Electrolytic - difficult if your are doing it commercially, where efficiency directly affects profit. If you're after a hundred grams of Mn, much
less of a problem. United States patents 2497725, 2750338, and 2810685 might be good starting points. This PDF http://www.recimat.org/pdf/S04/S04_10.pdf also might be interesting.
And if you want KMnO4 or NaMnO4, see http://pubs.acs.org/doi/abs/10.1021/j150206a002
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nightshade
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I woulld be very careful screwing with manganese doesn't cause nerve damage.
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Mr. Wizard
International Hazard
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Yes Nightshade, the link was between Parkinson's Disease and Manganese. It was called welder's disease or Manganism. There is also a link between
Parkinson's and some part of the brain 'substantia nigra'. There were also connections between synthetic heroin sales and some people who developed
Parkinson's Disease syndrome almost overnight. Many other chemicals are also implicated. Obviously a reason to be careful and limit exposure to dusts,
fumes and skin contact. I doubt anyone would show immediate symptoms from handling a little manganese dioxide, but it sure would be sad to spend the
end of your life with Parkinson's because of ignorance.
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nightshade
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My Father used welding rods and being a metalworker exposed to other metal oxides now seems to have a bad case of ALS.It doesn't take much to screw a
body up.
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